Patent GB-190226179-A (GB)
Title: Improvements in or relating to Typewriters and the like
Inventor: BOULT ALFRED JULIUS
Filed: 1902-11-27
Granted: 1903-02-05
Abstract: 26,179. Boult, A. J., [Spiro, C.]. Nov. 27. Type-writers.-Relates to the shift mechanism, inking-ribbon holders or guides, paper-feeding devices, and carriage scales of type-writers, and is described as applied to the "bar-lock" machine. The carriage in which the platen is mounted is supported by a rocking cradle B, Fig. 1, pivoted at B<1>. The shift-key lever A is secured to the cradle B, so that its depression rocks the platen forwards. To the free end of the lever A is pivoted at A<1> a subsidiary two-armed lever A<2>, which bears the finger keys A<3>, A'. The movement of the lever A<2> on its pivot is limited by the stops or lugs A<9> which project from it, and the lever also bears a spring-tensioned pawl A<6>. If the lever A is depressed by means of the key A<4>, the pawl A<6> is rocked sufficiently forwards to snap beneath the detent plate C' and maintain the platen in the shifted position. If the key A<3> is employed, the pawl is inactive, and the platen returns to the normal position when the pressure on the key is relaxed. More than one detent plate C<2> may be employed. In order that the oscillating ribbon arm or guide D may move far enough forwards to render the writing visible when the shift-key is depressed, as well as under normal conditions, it is pivotally mounted on the cradle B instead of being carried directly by the bail D<4>. Whenever a character key is depressed, the bail D<4> rocks downwards about its pivots D<2>, and its motion is communicated through the pin D' and arm B' to the arm D, which is pivoted at D<1> to a bracket B<3> secured to the cradle B. The ribbon is thus brought over the impression point. If the shiftkey is depressed and the cradle rocked forwards on its pivots B<1>, the arm D rocks forwards with it, the pin D' being for that purpose placed in axial line with the pivots B<1>. The relative position of the platen and the inking-ribbon is thus preserved. A screw B<5> holds the arms B<4>, D in rigid connection, and the hole in the arm B<4> through which it passes is slotted to allow room for adjustment. The carriage may be adapted to move backwards and forwards in a horizontal plane instead of being mounted in the cradle B. The paper-feeding devices and carriage scale are shown in Figs. 4 and 5. The feed-rollers E<2> are journalled in ears E<1> stamped up from a curved shell E. Elastic bands E<3> pass over the rollers, and bear against the surface of the platen. The shell E has a downward extension E<4>, which fits loosely in a groove F in one of the carriage members F<1>. A spring F<2> bears against the shell E, and the loose nature of the mounting enables the shell to align itself to the platen. The scale H is carried on arms H<1>. The scale is turned up on edge so that it rests on the paper in an approximately vertical position and conceals none of the writing. The scale is preferably engraved on the side remote from the operator, and is swung up on the arms H' when it is to be read. The face nearest the operator (that shown in Fig. 4) may, however, be engraved.